University of Calgary
Erasure coding techniques are used to increase the reliability of distributed storage systems while minimizing storage overhead. Also of interest is minimization of the bandwidth required to repair the system following a node failure. In a recent paper, the researcher characterizes the tradeoff between the repair bandwidth and the amount of data stored per node. They also prove the existence of regenerating codes that achieve this tradeoff. In this paper, the authors introduce exact regenerating codes, which are regenerating codes possessing the additional property of being able to duplicate the data stored at a failed node.